Device for tempering steam



Sept 8, 1953 w. c. GLovER, JR., ET Al.

DEVICE FOR TEMPERING STEAM Filed April 20, 1951 Patented Sept. 8, 1953 UNITED STATESPATENT OFFICE DEVICE Foa TEMPERING STEAM William C. Glover, Jr., Lees Summit, and Edwin G. Stevens, Independence, Mo., assignors to Bill Glover, Incorporated, a corporation of Missouri Application April 20, 1951, Serial No. 222,024

17 Claims. 1

This invention relates to steam processing apparatus, and more particularly to apparatus adapted to supply steam having different degrees of moisture content.

In certain mechanical and chemical processes, it is often desirable to have a constant steam supply, the moisture content of which can be varied from a relatively dry steam to one which is substantially saturated. The normal means by which this has been accomplished in the past has been to draw the tempering water from some part of the system where it has been collected as condensate and inject it into either the ilow lines or a suitable mixing chamber when it is picked up by the relatively dry vapor. it is desirable to control both the rate of discharge of the tempered steam and the amount of temperating water added, the use of a complex arrangement of separate controls and valves is required; and even where the valves have beenrelated to a single control, a complicated linkage involving considerable lost motion in correlating the timing is involved.

A primary object, therefore, of our invention is to provide a steam tempering device employing a single valving member which, at the will of the operator, may be positioned toobtain dry or tempered steam in the quantities and degrees of wetness desired.

Another object is to provide a valve device of novel construction, which is a simple, self-contained unitary structure adapted to be actuated by a single operating mechanism.

Still another object is to provide a device of this nature which can be easily connected to any steam supply system.

Other and further objects of our invention together with the features of novelty whereby the objects are achieved will appear in the course of the following description.

In the accompanying drawings which form a partl of the specification and are to be read .in conjunction therewith, and in which like reference numerals are employed to indicate like parts of the various views,

Fig. l is an elevational view partly in section, showing a device incorporating the features of our invention, n

Fig. 2 is an enlarged sectional view taken along the line 2 2 in Fig. l, in the direction of the arrows,

Fig. 3 is an enlarged fragmentary section of the valve assembly showing positions of the valving member for maximum flow of dry `steam and for tempering.

In systems where An important use of tempered steam is in the dry cleaning industry wherein it is employed to remove spots from garments and in treating the nap or pile of fabrics. In this connection, the illustrated embodiment of our invention has been developed for use in a garment spotting machine of the type disclosed in the copending application of AWilliam C'. Glover, Jr., Serial No. 150,504, filed March 19, 1950. It will be understood, oi course, that the device is not limited to this use alone, being similarly adaptable to use in any process wherein it is desirable to vary the moisture content of steam.

Referring now to the drawing, and more particularly to Fig. l, forming a reservoir for both dry steam and the tempering liquid is an elongated lcylindrical vessel I0 having a closed bottom Illa and a thickened head Illb. This vessel, hereinafter referred to as the steam separator, is secured to any suitable support, such as the frame of the spotting machine (not shown), in the upright position illustrated in the drawing, and

'pressurized dry steam is supplied thereto from a suitable source through an inlet pipe I2 threadedly received in a neck-like opening l0c formed in the separator wall. Inasmuch as the outer surface of the separator is exposed to ambient Y air, a portion of the steam entering condenses out and is collected at the bottom of the separator as condensate volume I4. As will be made clear presently, this condensate serves as the source of tempering liquidfor the device, being forced upward through a vertical tube I6 suspended centrally in the separator from inside a tempering valve housing (generally indicated by the numeral I8) connected to the upper end of the separator. An inverted cup-shaped intake housing I1 threadedly encircles the lower end of tube I6, and the bottom of the intake housing is covered by a suitable filter screen I'Ia.

The level Ma to which condensate may rise in the separator is controlled by an overflow pipe 20 connected tothe separator through a second threaded neck-like opening Illd spaced below the inlet opening I0c and leading to a suitable drain or to the source of the steam supply.

Secured to the upper end of the separator I0 and projecting axially thereabove is the tempering valve housing which is seen in detail in Fig. 2.

Forming the base element of the housing and having a slightly tapered lower end 22al threaded for insertion in a threaded axial opening in the head IIIb of the separator I0 (see Fig. l) is a sleeve member 22, the bore of which provides asteam iiow passageway 23 communicating at its lower end with the steam space in the separator. The upper end of sleeve 22 is counterbored approximately one-third of the bore length, providing an internal annular shoulder 22h, and a second sleeve 24 having a threaded bore 24a of substantially equal diameter with the counterbore axially abuts the upper end thereof. The sleeves are secured to one another by an vexternal icoupling nut 26 threadedly encircling the enlarged lower end 2411 of sleeve 24 and provided with an inturned iiange 26a which engages an annular shoulder 22e on the upper end of sleeve=22.

Screwed down substantially half-way into vthe bore 24a of the upper sleeve S211 is 'the Ythreaded cylindrical lower end 33a of'arelfativelyelongate valve body 3B having a continuous--axial'bore-'of varying size through which :extends 'an axially movable valve stem 32. While, as indicated at 34, valve stem 32 is received in a sliding -t 'above the nut-shaped medial portion 30h of the valve body, the bore is enlarged .therebelow to form an annular flow passageway 3B which flares at its lower end into an enlarged :threaded counterbore 30o adapted to receive a valve vseat member 38. Located intermediate the ends of the valve body and communicating with the upper end of flow passageway 36 is la lateral port 30d which is threaded to receive the end -of a flexible hose line leading to a hand operated steam discharge nozzle or gun (not shown).

It will be noted -that the bottom surface 35e of valve body 30 serves to define the upper lend of a substantially cylindrical chamber -40 formed by the connecting bores of sleeves ,22 and 24, the lower end of the chamber being dened by the annular shoulder 22h in the bore of the lower sleeve 22. Contained in chamber 40 and normally Vpositioned to close the valve body bore is a cylindrical valving member 42 into the upper end of which is threadedly inserted vthe lower end 32a of valve stem 32.

Steam flow into vthe valve body bore is sealed oi by an annular gasket 44 carried in a suitable .recess formed in the upper endof the valving member, the gasket seating `upwardly against an axially projecting annular bead 38a provided on the lower end of valve seat member 38. Directly above gasket .44, valve stem 32 vhas an integral enlarged shoulder or collar 46 which projects upwardly into the axial bore 38h of valve seat 38. It will be noted that collar 46 is slightly tapered from its base to its upper end, the base of the collar being designed to mate in a close fit with the bore 38h when the valve gasket A44 is seated against the valve seat bead 38a. The bore of the valve seat 38 above the portion 38h is cylindrical as indicated at 48, and provides a vpassageway communicating with the flow passageway 36 thereabove.

Examining now more in detail the parti-cular construction of valving member 42, provided near the lower end thereof is a relatively deep annular groove Eil which gives the appearance of dividing the member into two sections, viz., a valve head above the groove and, therebelow, a relatively thin disk-like structure 42a having its beveled lower edge B2b spaced above shoulder 22b at the lower end of chamber 40. As will be more fully discussed in describing the operation of the device, disk 42a serves as a throttling surface for restricting steam flow into chamber 4D after the valve gasket 44 has been unseated, the diameter of the disk being only slightly less than the diameter of the bore of sleeve 22 below shoulder 22D. (See Fig. 3.) Formed on the bottom of the disk structure 42a and projecting downwardly for a short distance into ilow passageway 23 is a short cylindrical section 42e of reduced diameter. An axial bore 52 extends upwardly through section 42o into the valving member, terminating slightly above the mid-point of the annular groove 50. and threadedly received therein is the upper end of "tube IB, which, as has .been hereinbefore described, extends downwardly through the separator into the condensate I4. A plurality of radial ducts 54 lead from the upper end of bore 52 into .the annular groove 5U, thus providing an open communication between chamber 40 and the interinrfof :tube 4Hi.

Vlli'oosely encircling valve stem 32 above valve body '3U and exerting an upward thrust thereon tto constantly :urge valving member 42 toward its seated position is a coiled compression spring 55. The :spring is retained at its upper end by a collar 58 threadedly secured to the valve stem near its upper end, and the lower end exerts a vdownward .thrust `on ya second collar 60 slidably encircling the vvalve .stem and also slidably received in the upper portion of an enlarged coun- -terbore 30f formed inthe upper end of valve body 3G. A compressible annular packing S2 encircles the stem below packing collar 60, and the downward thrust of the spring serves to provide a properseal around the stem at its entry into the stem guide portion 34 of the valve body.

Completely surrounding the spring assembly and slidably receiving the retaining collar 58 at its 44upper end as indicated at 64 is a lgenerally cylindrical housing 66 threadedly attached at its lower end 66a to the upper end of valve body 30. Interposed between kthe bottom `of the housing B6 and the upper surface of the nut-shaped medial portion 30h of the Valve body is the Icollar-like base leg 68a of .a generally L-shaped bracket 68, the vertical leg of which Vextends upwardly outside the spring housing 66. The upper end of bracket v68 is formed as a clevis having legs 68h, 68h and pivotally suspended therebetween on a .suitable bolt 'IB is a generally horizontal actuating lever 12, one end 12a of which overhangs a dome-like cap nut 'I4 secured to the end of the valve stem 32, and the other end of which is drilled as .indicated at 16 for attachment to a suitable operating linkage.

Spaced below the actuating lever 'l2 and freely riding on .bracket E8 between the clevis ears 68h, 68h, is a plate-like member 18, whose contoured outer end '18a is interposed between the operating lever and the top of cap nut '14. The opposite end of member 'I8 is turned downwardly as indicated at 18h and is disposed between the side of the bracket Yand a downwardly projecting spur rigidly secured to the under side of the actuating lever. Inasmuch as during operation of the actuating lever some wear will take place between end 12a of the lever and the adjacent surface of member 18, the latter is preferably formed from stainless steel or a similarly wear-resistant material.

In use with a spotting machine adapted to be equipped with our invention, the free end of the actuating lever 'I2 is connected by a push-rod linkage (not shown) to a pedal at the bottom of the machine adapted to be operated by the foot of the operator, thus freeing his hands for manipulation of the steam gun and the fabric being treated.

In the operation of the device, steam from a suitable source is introduced under pressure into the separator Ill through inlet pipe l2. As here- -ber 38.

inbefore described, partial condensation takes place within the separator, the condensate collecting at the bottom and rising to level I4a, at which point excess condensate is disposed of through overflow pipe 20. take I1 connected to the bottom of tube I6 is wholly immersed in the condensate, and inasmuch as the pressure in valve chamber 40 is initially equal to that in the separator, condensate is also contained in tube I6 to level I4a, the steam pressure in valve chamber 40 being communicated to the interior of tube I6 through the radial ducts '54 in valving member 42.

Assuming that a steam gun such as is used in spotting machines of the type hereinbefore referred to is connected by a exible line to discharge port 30d in valve body 30, either dry or tempered steam may be delivered to the gun by pivoting the actuating lever 'I2 about its axis to depress the valving member 42 against the action of spring 56. Whether dry or tempered steam is delivered to the gun depends on the extent of displacement of the valving member, as will be discussed hereinafter.

As may best be appreciated from Fig. 3, during the initial downward motion of valving member 42, valve gasket 44 is unseated and steam discharges from chamber 40 through an annular passageway formed between the tapered surface of collar 46 and the bore 38h of valve seat mem- The rate of flow of the discharging steam is governed by the vertical position of collar 46 relative to bore 38h, increasing from a minimum at the point of unseating to a maximum when the valving member occupies the position indicated by the solid lines in Fig. 3. While, as shown therein, the upper end of collar 4B still is within bore 38h, the size of the opening therebetween is now sufficient to completely satisfy the discharge 'capacity of the steam gun, and any further downward movement of the washer will not result in an increased steam fiow from the device.

Concurrently with collar 46 reaching the position shown in Fig. 3, the lower surface of the throttling disk 42a on the valving member reaches a position substantially level with the annular shoulder 22h at the bottom of chamber 40. While the size of the steam inlet opening to chamber 40 is now somewhat restricted in comparison with the size of the opening when the valving member is in normal position, it should be understood that this inlet still is capable of supplying steam to the chamber as fast as it is being exhausted at the upper end; consequently, the pressure in chamber 4D remains substantially equal to that in the separator. The condensate in tube I6 therefore still remains at level I4a, and dry steam is all that is discharged from the device.

To supply tempered steam to the discharge gun or nozzle, the operator need only depress the valving member below the position shown by solid lines in Fig. 3. The size of the steam inlet into chamber 40 is gradually reduced as the beveled lower edge 42h of the throttling disk 42a moves past shoulder 22h, and steam is discharged from the upper end of the chamber faster than it is vbeing supplied, thus resulting in a decreasing pressure in chamber 4U. Inasmuch as the pressure in the separator remains at a relatively higher value, the condensate is forced upwardly through tube I6 and discharged through ducts 54. The condensate is picked up by the steam flowing through the chamber, and is carried to the steam The cup-shaped in- .6 gun where it may be directed over the fabric being treated.

The amount of water mixed with the steam depends on the position of the throttling disk 42a relative to shoulder 22h, the major variation taking place through a displacement represented by the width of the beveled edge i219l of the disk. However, even after the upper edge of the beveled surface reaches an equal level with the shoulder, some additional throttling is obtained as the disk portion 42a moves downwardly into flow passageway 24 to the position shown by the broken lines in Fig. 3. This is primarily due to an increased friction loss in the flowing steam which results from the lengthening of the annular passageway formed between the periphery of disk 42a and the wall of flow passageway 24.

In connection with the throttling of steam flow into chamber 40, it is important to note that while the range through which tempered steam is obtained represents a relatively small displacement of valving member 42, the length of the actuating lever 'I2 is such that an appreciably greater displacement of the operating linkage (and foot pedal) will be required. Thus an operator may, without being required to exercise undue sensitivity, accurately position the valving member to obtain the steam quality desired.

From the foregoing it will be seen that this invention is one well adapted to attain all of the ends and objects hereinabove set forth together with other advantages which are obvious and which are inherent to the invention.

It will be understood that certain features and subcombinations are of utility and may be employed without reference to other features and subcombinations. This is contemplated by and is within the scope of the claims.

As many possible embodiments may be made of the invention without departing from the scope thereof, it is to be understood thatV all matter herein set forth or shown in the accompanying drawings is to be interpreted as illustrative and not in a limiting sense.

Having thus described our invention, we claim:

1. Apparatus of the character described, comprising a pair of chambers disposed one above the other with a restricted vertical passageway therebetween, the lower one of said chambers comprising an enclosed vessel having a source of steam under pressure connected to the upper portion thereof, whereby condensate is adapted to collect in the lower portion of the vessel, means for limiting the maximum level which the condensate can attain in said vessel, the upper chamber having an outlet port restricted in size relative to said passageway, whereby steam can pass from said lower chamber through said passageway into the upper chamber and escape through said port, a valving member in one of said chambers normally spaced vertically from said passageway but movable toward said passageway to throttle said flow of steam into the upper chamber, a vertical conduit extending through said valving member and passageway and secured to said valving member to move therewith, the upper end of said conduit opening into said upper chamber and the lower end of theY conduit being immersed in the condensate in the lower chamber.

2. Apparatus of the character described, comprising a pair of chambers disposed one above the other with a restricted vertical passageway therebetween, the lower one of said chambers `comprising fan enclosed vessel having a source of steam under pressure connected to the upper .portion thereof whereby condensate collects in the lower portion, means for limiting the maximum level which the condensate can attain in the vessel, the upper chamber having an outlet port restricted in size relative to said passageway, a normally seated valve associated with said port and having integral therewith a throttli'ng member normally spaced vertically from said passageway, means for moving said valve vertically to unseat same and optionally continuing said movement to advance said member into throttling relation to said passageway, said valve effective upon being unseated to permit steam to flow from the upper portion of said lower chamber through said passageway into the upper chamber and escape through said port, and said throttling member adapted upon Said continued movement to restrict the ilow of steam through said passageway, a vertical conduit extending through said throttling member vand lpassageway and secured to the throttling member to move therewith, the upper end of the conduit opening into said upper chamber and the lower end of the conduit being immersed in the condensate in the lower chamber.

3. Apparatus of the character described, comprising a pair of chambers disposed one above the other with a restricted vertical passageway therebetween, the lower one of said chambers comprising an enclosed vessel containing a liquid and, above the surface of the liquid, a fluid under pressure, the upper` chamber having an outlet port restricted in size relative to said passageway, where'by uid can pass from the upper part of the lower chamber through said pas- -sageway into the upper chamber and escape through said port, a valving member in one of said chambers normally spaced vertically from said passageway but movable toward said passageway to throttle said flow of fluid into the upper chamber, a vertical conduit extending through said valving member and passageway and secured to said valving member to move therewith, the upper end of said conduit opening into said upper chamber and the lower Aend `of the conduit being immersed in the liquid in the lower chamber.

4. Apparatus of the character described, comprising an enclosed vessel containing a liquid and, above the surface of the liquid, a fluid un- 'der pressure, an enclosed chamber, at least a portion of said chamber being positioned above said vessel, a passageway extending vertically downward from said portion of the chamber to the fluid 'space in the upper portion of said vessel whereby said llu'id is admitted to said chamber, said chamber having an outlet port for said uid, which port is restricted in size relative to said passageway, a valve associated with said passageway and vertically movable to throttle the iiow of said iluid from the vessel into said chamber, a vertical duct extending through said valve and open only at its upper and lower ends, the open upper end of the duct being above the valve and within said chamber, and the open lower -end of the duct being immersed in the liquid in the bottom of said vessel.

5. Apparatus of the character described, comprising an enclosed vessel containing a, liquid and, `above the surface of the liquid, a fluid under DIES- -sure, an enclosed chamber, at least a portionf vsaid chamber -being positioned above said vessel, a passageway extending vertically downward from said portion of lthe chamber to the fluid space in the upper portion of the vessel whereby said -iluid is admitted tosaid chamber, said chamber having an outlet port for said fluid, which port is restricted in size relative to said passageway, a valve associated with said passageway and vertically movable to throttle the flow of said iluid from the vessel into the said chamber, a vertical tube having its upper end secured to said valve to move therewith, the open lower end of said tube being immersed in the liquid in the lower part of said vessel, and apassageway 'extending from the upper end of said tube through the valve into the interior of s'aid chamber whereby said throttling of the fluid ilow causes said liquid to iiow upwardly through the tube -and be discharged into the chamber.

'6. Apparatus of the character described, comprising an enclosed vessel containing a liquid and, above the surface of the liquid, a fluid under pressure, an venclosed chamber, at least a portion of said chamber being positioned above ysaid vessel, a passageway extending vertically downward from said portion of the chamber to the fluid space in the upper portion of said vessel whereby said iiuid is admitted to the chamber, said chamber having an outlet port for said uid and a valve associated with the port for opening and closing same, a discharge passageway through which said fluid flows from said chamber when the valve is open, said last passageway being restricted in size relative to said iirst passageway, a valve associated with said rst passageway and vertically movable to throttle the ow of said fluid from the vessel into said chamber, a vertical duct extending through said second valve and open only at its upper and lower ends, the open upper end of the duct being above the second valve and within said chamber, and the open lower end of the duct being immersed in the liquid in the bottom of the vessel.

'l'. Apparatus of the character described, comprising an enclosed vessel containing a liquid and, above the surface of the liquid, a fluid under pressure, an enclosed chamber, at least a portion of said chamber being positioned above said vessel, a passageway extending vertically downward from said portion of the chamber to the fluid space in the upper portion of said vessel whereby said iiuid is admitted to the chamber, said chamber having an outlet port for said fluid and a valve associated with the port for opening and closing same, a discharge passageway through which said uid flows from said chamber when the Valve is open, said last passageway being restricted in size relative to said first passageway, a valve associated with said first passageway and vertically movable to throttle the flow of said fluid from the vessel into said chamber, a vertical tube having its upper end secured to said second valve to move therewith, the open lower end of said tube being immersed in the liquid in the lower part of said vessel, and a passageway extending from the upper end of the tube through said second valve into the `interior of said chamber whereby said throttling of the fluid ow causes said liquid to flow upwardly through the tube and be discharged into the chamber.

8. Apparatus of the character described, comprising a vessel containing a liquid and, above the surface of the liquid, a itluid under pressure,

an enclosed chamber above the vessel having an inlet port in the bottom thereof, a passageway extending vertically downward from said port to the fluid space in the upper portion of the vessel whereby said fluid can pass from the vessel into said chamber, said chamber having an outlet port spaced above the passageway in vertical alignment therewith, a valve in said chamber normally closing said port but movable downwardly to open same, a discharge passageway through which said fluid ow from said chamber when the valve is open, said last passageway being restricted in size relative to said first passageway, a second valve in said chamber normally spaced above said inlet port but linked to said first valve to move downwardly therewith, said second valve constructed and arranged upon. such downward movement to throttle the iiow of fluid through said iirst passageway after a predetermined downward m-ovement of said second valve, a vertical duct extending through said second valve and open only at its upper and lower ends, the open upper end of the duct being above the second valve and within said chamber,

and the open lower end of the duct being im` mersed in the liquid in the bottom of said vessel.

9. Apparatus of the character described, comprising a vessel containing a liquid and, above the surface of the liquid, a fluid under pressure, an enclosed chamber above the vessel having an inlet port in the bottom thereof, a passageway extending vertically downward from said port to the fluid space in the upper portion of the vessel whereby said iluid can pass from the vessel into said chamber, said chamber having an outlet port spaced above the passageway in vertical alignment therewith, a valve in said chamber normally closing said port but movable downwardly to open same, a discharge passageway through which said fluid flows from said chamber when the valve is open, said last passageway being restricted in size relative to said rst passageway, a second valve in said chamber normally spaced above said inlet port but linked to said first valve to move downwardly therewith, a vertical tube having its upper end secured to said second valve to move therewith, the open lower end of said tube being immersed in the liquid in the lower part of said Vessel, and a passageway extending from the upper end of the tube through said second valve into the interior of said chamber whereby said throttling of the iiuid flow'causes said liquid to flow upwardly through the tube and be discharged into said chamber.

10. Apparatus of the character described, comprising a vessel containing a liquid and, above the surface of the liquid, a fluid under pressure, a body mounted on the top of said Vessel and containing a bore extending vertically upward from the fluid space in the upper part of said vessel, said bore being enlarged in a limited region intermediate its upper and lower ends to form a mixing chamber, an upwardly seating valve member in said chamber for normally sealing said chamber off from the portion of the bore above the chamber, the bottom of said valve member being normally spaced above the bottom of the chamber and the sides of the valve member being spaced inwardly from the sides of the chamber, a vertical conduit secured at its upper end to the bottom of the valve member and having its lower end immersed in the liquid in said vessel, at least one passageway extending from the upperend of said con-l duit laterally through said valve member and opening into the space -between the side wall of the Valve member and the side wall of the chamber, means for movingpsaid valve member vand conduit downwardly as a unitthereby to unseat' the valve and optionally continuing such movement to cause the lower portion .of the valve memberto enter the portion of the bore below said chamber, said lower portion of the valve member -being only slightly smaller Yin size than said lower portion of the bore whereby it is adapted to throttle the flow of fluid from the upper portion of said vessel into the chamber.

11. Apparatus of the character described, comprising a vessel containing a liquid and, above the surface of the liquid, a fluid under pressure, a body mounted on the top of said vessel and containing a bore extending vertically upward from the fluid space in the upper part of said vessel, said bore -being enlarged in a limited region intermediate its upper and lower ends to form al mixing chamber, an upwardly seating valve member within said chamber for normally sealing said chamber off from the portion of the bore above the chamber, said valve comprising a plug whose lower end is normally spaced above the -bottom of the chamber and whose sides are spaced inwardly from the sides of the chamber, said plug having intermediate its top and bottom an annulargroove, a vertical.r conduit secured at its upper end to the bottom of said plug and having its lower end immersed in the liquid in said vessel, apassageway through said plug extending from the upper end of said conduit into the bottom of said groove, means for moving said'plugand conduit downwardly as a unit to unseat the valve'and optionally continuing said movement to advance the portion of the plug below said groove into the portion vof said bore below said chamber, said last portion of the plug being only slightly smaller in size than said last portion of the bore whereby it is adapted to throttle the flow of fluid from the upper part of said vessel into'saidV chamber.

12.. Apparatus as in claimll wherein said-plug has an upwardly tapered portion which projects into the portion `of said bore extending upwardly let and outlet ports on opposite sides thereof,A

fluid inlet and outlet passageways associated with the respective portssaid outlet passageway being restricted in size relative to said inlet passageway, a normally seated outlet valve associated with the outlet port, said valve having integral therewith a throttling member disposed in said chamber and normally spaced from said inlet port, meansA for moving said outlet valve toward said inlet port thereby to unseat same and optionally continuing said movement to advance said member into throttling relation to said inlet port, a source of fluid under pressure connected to said inlet passageway whereby unseating of said valve permits iluid from said source to enter said chamber 4and escape through said outlet port, said member effective when advanced into throttling relation to said inlet port to reduce the effective size of the ilow passageway through said inlet port below the size of said outlet passageway, a tube extending through said inlet passageway and having one end secured to said member to move therewith, a passageway from said one end of said tube extending through said mein-ber andY opening into said chamber, anda second source of fluid un-Y der pressureY connected to thev other end of said tube for causing said` last fluid to iiovv through said tube into said chamber when said member is advanced into throttling relation to said inlet port.

14. Apparatus of the character described, comprising a chamber having aligned ports on opposite sides thereof, a plug within said charnber movable 'along al path aligned with. said ports, an annular seat around one of the ports adapted to be engaged by one end of the plug upon movementof same'in one direction thereby to close said one p'crt, the other end of the plug being smaller inY size than the other port whereby it enters and partially closes said other port upon movement cf the plug in the opposite direction, a rigidV tubeextending into said chamber through one of said ports and having its end secured to the plug whereby the 'tube moves with the plug, said plug havingY a lateral bore'communc'ating at oneV endwith said tube and opening at the other end through the side wall of the plug intermediate the opposite ends of the plug, said sidewall ot the plug being spaced inwardly from the side Wall of the chamber.

15. Apparatus of the character described, comprising a chamber. having. aligned. ports on opposite sides thereof, a plug within said, chamber movable along a path aligned with saidA ports, an annular seat around one! of theports adapted to be engaged by one end of, the plug upon move:- ment of same in one direction thereby to close said one port, said one port` comprising a bore leading away from said. chamber, said plug have ing a tapered projection which extends into said bore and seats against same when said end of the plug engages said annular seat, the other end of the plug being smaller in size than the other port whereby it enters and partially closes said other port upon movement. of the plug in the opposite direction, a rigid. tube extending into said chamberthrough oneof-said-,ports and having its end secured to the plugw-hereby` the tube moves with the plug,A said. plug having. a

lateral bore communicating at one endwithV said. tube and opening at the other endthrough the.

side wall of theplug intermediatev the. opposite ends ofthe plug, said side wall of; the plugv being spaced inwardly from the side wall of, the chamber.

16. Apparatus of'thecharacter described,- comprising a generally cylindrical chamber having aligned ports at opposite endsthereof, a general# ly cylindrical plug in said chamber 'coaxial 'with said ports, said plug being smaller in diameter and shorter in length than the chamber, one of said ports being smaller Vin diameter than the plug and encircled by a seat adapted to be engagedby the end of the plug upon movement of same toward said one port thereby to close saidv one port, the other port being larger in, diameter than the plug whereby the plug is adapted to advance thereintc and partially close said other port upon movement of the plug in the opposite direction, a rigid tube extending into said chamber through one of said ports and having its endsecured to the plug whereby' the tube and plug move together as a unit, said plughaving a lateral bore communicating at one end with saidv tube and opening at the other end through the side wall of the plug intermediate its opposite ends.

17. Apparatus of the character described, com-L prising a generally cylindrical chamber having aligned ports at opposite ends thereof a generally cylindrical plug in said chamber coaxial with said` ports, said plug being smaller in diameter and shorter in length than the chamber, saidY plug having intermediate its ends an annular groove circumscribing the plug, one of said ports being smaller in diameter than the plug and encircled by a seat adapted to be engaged-by the end of the plug upon movement of salme'toward said one port,4 thereby to close said one porig'the` other port being larger in diameter than the plug whereby the end portionoi the plug on one side of said groove is adapted to advancer into and partially close said other port upon movement of the plug in the opposite direction, a rigid tube extending intodsad; chamber through one of said ports and having its end secured to the plug whereby saidvtube and plug move together as a u nit, said plug having alateral bore communicating at one end with said tube and Opening at the other end into said groove.

WILLIAM c. G LovnR, JR. EDWIN G. STEVENS.

References Cited in the file of this patent UNITED STATES PATENTS` Number l Name Date,

1,923,422 Conley et al. Aug. 2.2, 1933 2,345,821v Cissell Apr. 1.8, 19de, 2,391,663. Weber et a1. Dec. 25, 1945, 21,455,754 Glover Dec. 7, 1944.8 

